What happens as a result of an increase in the intensity of a sound wave? -the frequency of a soundwave increases. -the velocity of the sound wave decreases. -the energy of the soundwave increases. -the amplitude of the soundwave decreases

Automobile fuel efficiency is often measured in miles that the car can be driven per gallon of fuel (mpg). heavier cars tend to have lower fuel efficiencies (lower mpg ratings). which variable (weight or fuel efficiency) is most naturally considered the explanatory (predictor) variable in this context?